Obesity and its frequent sequelae: metabolic syndrome and Type-2 diabetes have progressively become the major health concern in developed and even in underdeveloped countries. The purpose of this project is to address the assessment and reduction of cardiovascular risk in individuals that are already presumably at high risk to develop Coronary Heart Disease (CHD) due to existing metabolic syndrome. The focus of the proposed project is to evaluate components of high-density lipoprotein (HDL) metabolism as selection criteria for fibrate therapy in an attempt to raise plasma high density lipoprotein (HDL) levels. The proposed studies will utilize the recruitment populations from Project by Smith and will address the following two specific aims: AIM 1. Determine the fractional plasma cholesterol esterification (PER) rates in the selected study population and correlate the findings with the size distribution in the high-density lipoprotein pool. AIM 2. Determine the projected impact of gemfibrozil therapy on the individual subjects within minority populations with and without metabolic syndrome and/or sleep disordered breathing by assessing the PER rates and size distribution of the HDL particles.